Suppose I have a file info.txt. The first column is the id, and the rest are its content.
1 aaa bbb
1 ccc ddd mmm
4 ccc eee
7 ddd fff jjj kkk
I'm only intereted with the lines beginning with "1". So I use grep to filter it:
what_I_concern=$(cat info.txt | grep -iw 1 | cut -d ' ' -f 2-)
and then I want to iterate through these lines:
for i in $what_I_concern; do
pass $i to another program #I want to pass one line at a time
done
But what it really did is to iterate through every word in these lines, instead of taking each line as a whole.
How can I solve this problem?
The way you're trying to accomplish what you need is causing word splitting. Instead, say:
while read -r line; do
someprogram $(cut -d' ' -f2- <<< "$line")
done < <(grep '^1' info.txt)
The <() syntax is known as Process Substitution. In this case, it enables the while loop to read the output of the grep command as a file.
You can avoid using grep and cut altogether in this case (assuming default IFS)
while read -r first rest; do
[ "$first" = "1" ] && pass "$rest" to another program;
done < info.txt
Related
I'm trying to write a very small program that will check the number of sub strings in a large text file. All it will do is count the first 2000 lines of the text file, find any "TTT" sub-strings, count them, and set a variable to that total. I'm a bit new to shell, so any help would be amazingly appreciated!
#!/bin/bash
$counter=(head -2000 [file name] | grep TTT | grep -o TTT | wc -l)
echo $counter
For what it's worth you might awk better suited for this task:
awk -F"ttt" '{j=(NF-1)+j}END{print j}' filename
This will split each record in your file by delimiter "ttt". Then it counts the number of fields, subtracts one, and adds that to the total.
A file like:
ttt tttttt something
1 5 ttt
tt
one more ttt record
Would be split (visualizing with pipe delim) like:
| || something
1 5 |
tt
one more | record
Counting the number of fields per record:
4
2
1
2
Subtracting one from that:
3
1
0
1
Which totals to 5, which is how many "ttt" substrings are present.
To incorporate this into your script (and fixing your other issue):
#!/bin/bash
counter=$(awk -F"ttt" '{j=(NF-1)+j}END{print j}' filename)
echo $counter
The change here is that when we set a variable in Bash we don't include the $ sign at the front. Only in referencing the variable do we include the $.
You have some minor syntax errors there, probably you meant this:
counter=$(head -2000 [file name] | grep TTT | grep -o TTT | wc -l)
echo $counter
Notice the tiny changes I made there to make it work.
Btw the grep TTT in the middle is redundant, you can simply drop it, that is:
counter=$(head -2000 [file name] | grep -o TTT | wc -l)
grep can already do what you want: counter=$(grep -c TTT $infile). You can limit the number of hits (not lines) with -m NUM, --max-count=NUM, which makes grep stop at the end of the file OR when NUM occurrences are found.
I have a file in Linux contains strings:
CALLTMA
Starting
Starting
Ending
Starting
Ending
Ending
CALLTMA
Ending
I need the quantity of any string (FE. #Ending, # Starting, #CALLTMA). In my example I need obtaining:
CALLTMA : 2
Starting: 3
Ending : 4
I can obtaining this output when I execute 3 commands:
grep -i "Starting" "/myfile.txt" | wc -l
grep -i "Ending" "/myfile.txt" | wc -l
grep -i "CALLTMA" "/myfile.txt" | wc -l
I want to know if it is possible to obtain the same output using only one command.
I try running this command
grep -iE "CALLTMA|Starting|Ending" "/myfile.txt" | wc -l
But this returned the total of coincidences. I appreciate your help .
Use sort and uniq:
sort myfile.txt | uniq -c
The -c adds the counts to the unique lines. If you want to sort the output by frequency, add
| sort -n
to the end (and change to -nr if you want the descending order).
A simple awk way to handle this:
awk '{counts[$1]++} END{for (c in counts) print c, counts[c]}' file
Starting 3
Ending 4
CALLTMA 2
grep -c will work. You can put it all together in a short script:
for i in Starting CALLTMA Ending; do
printf "%-8s : %d\n" "$i" $(grep -c "$i" file.txt)
done
(to enter the search terms as arguments, just use the arguments array for the loop list, e.g. for i in "$#"; do)
Output
Starting : 3
CALLTMA : 2
Ending : 4
I'm writing a shell script traversing a list of directories and counting words from files inside them. The code prints data each time I read a file. So the output is not sorted. How can I sort it?
The output right now is like this:
cat 5
door 1
bird 3
dog 1
and I want to sort it first by second column and then by first column:
dog 1
door 1
bird 3
cat 5
You can pipe your shell script to:
sort -n -k2 -k1
With -n you specify numeric sort and with -k2 that you want to sort first by the second field and with -k1 to sort then by first field.
First of all, I tried to reproduce what OP is doing, so after creating the files, I tried this command:
% for i in *; do echo -n "$i "; wc -w < $i; done
bird 3
cat 5
dog 1
door 1
Then I have added the sort:
% (for i in *; do echo -n "$i "; wc -w < $i; done) | sort -n -k 2 -k 1
dog 1
door 1
bird 3
cat 5
I have already tried all options that I found online to solve my issue but without good result.
Basically I have two csv files (pipe separated):
file1.csv:
123|21|0452|IE|IE|1|MAYOBAN|BRIN|OFFICE|STREET|MAIN STREET|MAYOBAN|
123|21|0453|IE|IE|1|CORKKIN|ROBERT|SURNAME|CORK|APTS|CORKKIN|
123|21|0452|IE|IE|1|CORKCOR|NAME|HARRINGTON|DUBLIN|STREET|CORKCOR|
file2.csv:
MAYOBAN|BANGOR|2400
MAYOBEL|BELLAVARY|2400
CORKKIN|KINSALE|2200
CORKCOR|CORK|2200
DUBLD11|DUBLIN 11|2100
I need a linux bash script to find the value of pos.3 from file2 based on the content of pos7 in file1.
Example:
file1, line1, pos 7: MAYOBAN
find MAYOBAN in file2, return pos 3 (2400)
the output should be something like this:
**2400**
**2200**
**2200**
**etc...**
Please help
Jacek
A little approach, far away to be perfect:
DELIMITER="|"
for i in $(cut -f 7 -d "${DELIMITER}" file1.csv );
do
grep "${i}" file2.csv | cut -f 3 -d "${DELIMITER}";
done
This will work, but since the input files must be sorted, the output order will be affected:
join -t '|' -1 7 -2 1 -o 2.3 <(sort -t '|' -k7,7 file1.csv) <(sort -t '|' -k1,1 file2.csv)
The output would look like:
2200
2200
2400
which is useless. In order to have a useful output, include the key value:
join -t '|' -1 7 -2 1 -o 0,2.3 <(sort -t '|' -k7,7 file1.csv) <(sort -t '|' -k1,1 file2.csv)
The output then looks like this:
CORKCOR|2200
CORKKIN|2200
MAYOBAN|2400
Edit:
Here's an AWK version:
awk -F '|' 'FNR == NR {keys[$7]; next} {if ($1 in keys) print $3}' file1.csv file2.csv
This loops through file1.csv and creates array entries for each value of field 7. Simply referring to an array element creates it (with a null value). FNR is the record number in the current file and NR is the record number across all files. When they're equal, the first file is being processed. The next instruction reads the next record, creating a loop. When FNR == NR is no longer true, the subsequent file(s) are processed.
So file2.csv is now processed and if it has a field 1 that exists in the array, then its field 3 is printed.
You can use Miller (https://github.com/johnkerl/miller).
Starting from input01.txt
123|21|0452|IE|IE|1|MAYOBAN|BRIN|OFFICE|STREET|MAIN STREET|MAYOBAN|
123|21|0453|IE|IE|1|CORKKIN|ROBERT|SURNAME|CORK|APTS|CORKKIN|
123|21|0452|IE|IE|1|CORKCOR|NAME|HARRINGTON|DUBLIN|STREET|CORKCOR|
and input02.txt
MAYOBAN|BANGOR|2400
MAYOBEL|BELLAVARY|2400
CORKKIN|KINSALE|2200
CORKCOR|CORK|2200
DUBLD11|DUBLIN 11|2100
and running
mlr --csv -N --ifs "|" join -j 7 -l 7 -r 1 -f input01.txt then cut -f 3 input02.txt
you will have
2400
2200
2200
Some notes:
-N to set input and output without header;
--ifs "|" to set the input fields separator;
-l 7 -r 1 to set the join fields of the input files;
cut -f 3 to extract the field named 3 from the join output
cut -d\| -f7 file1.csv|while read line
do
grep $line file1.csv|cut -d\| -f3
done
Acttualy this is my assignment.I have three-four file,related by student record.Every file have two-three student record.like this
Course Name:Opreating System
Credit: 4
123456 1 1 0 1 1 0 1 0 0 0 1 5 8 0 12 10 25
243567 0 1 1 0 1 1 0 1 0 0 0 7 9 12 15 17 15
Every file have different coursename.I did every coursename and studentid move
in one file but now i don't know how to add all marks and move to another file on same place where is id? Can you please tell me how to do it?
It looks like this:
Student# Operating Systems JAVA C++ Web Programming GPA
123456 76 63 50 82 67.75
243567 80 - 34 63 59
I did like this:
#!/bin/sh
find ~/2011/Fall/StudentsRecord -name "*.rec" | xargs grep -l 'CREDITS' | xargs cat > rsh1
echo "STUDENT ID" > rsh2
sed -n /COURSE/p rsh1 | sed 's/COURSE NAME: //g' >> rsh2
echo "GPA" >> rsh2
sed -e :a -e '{N; s/\n/ /g; ta}' rsh2 > rshf
sed '/COURSE/d;/CREDIT/d' rsh1 | sort -uk 1,1 | cut -d' ' -f1 | paste -d' ' >> rshf
Some comments and a few pointers :
It would help to add 'comments' for each line of code that is not self evident ; i.e. code like mv f f.bak doesn't need to be commented, but I'm not sure what the intent of your many lines of code are.
You insert a comment with the '#' char, like
# concatenate all files that contain the word CREDITS into a file called rsh1
find ~/2011/Fall/StudentsRecord -name "*.rec" | xargs grep -l 'CREDITS' | xargs cat > rsh1
Also note that you consistently use all uppercase for your search targets, i.e. CREDITS, when your sample files shows mixed case. Either used correct case for your search targets, i.e.
`grep -l 'Credits'`
OR tell grep to -i(gnore case), i.e.
`grep -il 'Credits'
Your line
sed -n /COURSE/p rsh1 | sed 's/COURSE NAME: //g' >> rsh2
can be reduced to 1 call to sed (and you have the same case confusion thing going on), try
sed -n '/COURSE/i{;s/COURSE NAME: //gip;}' rsh1 >> rsh2
This means (-n don't print every line by default),
`gip` = global substitute,
= ignore case in matching
print only lines where substituion was made
So you're editing out the string COURSE NAME for any line that has COURSE in it, and only printing those lines' (you probably don't need the 'g' (global) specifier given that you expect only 1 instance per line)
Your line
sed -e :a -e '{N; s/\n/ /g; ta}' rsh2 > rshf
Actually looks pretty good, very advanced, you're trying to 'fold' each 2 lines together into 1 line, right?
But,
sed '/COURSE/d;/CREDIT/d' rsh1 | sort -uk 1,1 | cut -d' ' -f1 | paste -d' ' >> rshf
I'm really confused by this, is this where you're trying to total a students score? (with a sort embedded I guess not). Why do you think you need a sort,
While it is possible to perform arithmetic in sed, it is super-crazy hard, so you can either use bash variables to calculate the values OR use a unix tool that is designed to process text AND perform logical and mathematical operations of the data presented, awk or perl come to mind here
Anyway, one solution to total each score is to use awk
echo "123456 1 1 0 1 1 0 1 0 0 0 1 5 8 0 12 10 25" |\
awk '{for (i=2;i<=NF;i++) { tot+=$i }; print $1 "\t" tot }'
Will give you a clue on how to proceed for that.
Awk has predefined variables that it populates for each file, and each line of text that it reads, i.e.
$0 = complete line of text (as defined by the internal variables RS (RecordSeparator)
which defaults to '\n' new-line char, the unix end-of-line char
$1 = first field in text (as defined by the internal variables FS (FieldSeparator)
which defaults to (possibly multiple) space chars OR tab char
a line with 2 connected spaces chars and 1 tab char has 3 fields)
NF = Number(of)Fields in current line of data (again fields defined by value of FS as
described above)
(there are many others, besides, $0, $n, $NF, $FS, $RS).
you can programatically increment for values like $1, $2, $3, by using a variable as in the example code, like $i (i is a variable that has a number between 2 and NF. The leading '$'
says give me the value of field i (i.e. $2, $3, $4 ...)
Incidentally, your problem could be easily solved with a single awk script, but apparently, you're supposed to learn about cat, cut, grep, etc, which is a very worthwhile goal.
I hope this helps.